From 1ac2de6cef6c9f34999bd27e0c72e452a6397458 Mon Sep 17 00:00:00 2001
From: Peter Bittner <django@bittner.it>
Date: Wed, 11 Nov 2026 20:40:26 +0100
Subject: [PATCH] Clean up coverage data files of parallel runs

With pytest-xdist, coverage writes one data file per process, named
`.coverage.<host>.pid<pid>.X<random>x`, optionally followed by `.H<hash>h`.
Without `coverage combine`, they stay behind. The coverage topic now removes
them, but not `.coveragerc` or other files.
---
 README.rst           |  2 +-
 pyclean/debris.py    |  1 +
 tests/test_debris.py | 21 +++++++++++++++++++++
 3 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/README.rst b/README.rst
index 7d24bac..e5b72d6 100644
--- a/README.rst
+++ b/README.rst
@@ -200,7 +200,7 @@ popular Python development tools in their default locations, along with
 Python bytecode. The following topics are currently covered:
 
 - Cache (general purpose folder for several tools, e.g. Python eggs, legacy Pytest)
-- Coverage (coverage database, and supported file formats)
+- Coverage (coverage database, also of parallel runs, and supported file formats)
 - Packaging (build files and folders)
 - Pytest (build files and folders)
 - Ruff (ruff cache folder)
diff --git a/pyclean/debris.py b/pyclean/debris.py
index c16cd08..ef8c041 100644
--- a/pyclean/debris.py
+++ b/pyclean/debris.py
@@ -25,6 +25,7 @@
     ],
     'coverage': [
         '.coverage',
+        '.coverage.*.pid*.X*',
         'coverage.json',
         'coverage.lcov',
         'coverage.xml',
diff --git a/tests/test_debris.py b/tests/test_debris.py
index 5baa565..7c5f5ba 100644
--- a/tests/test_debris.py
+++ b/tests/test_debris.py
@@ -106,6 +106,27 @@ def test_debris_recursive():
         assert dir_nested_topic.parent.exists()
 
 
+def test_debris_coverage_parallel_data_files():
+    """
+    Are the data files of parallel coverage runs deleted, but not the
+    coverage configuration?
+    """
+    with TemporaryDirectory() as tmp:
+        directory = Path(tmp)
+        data_files = [
+            directory / '.coverage.myhost.pid1234.XqzCbEdx',
+            directory / '.coverage.myhost.pid1234.XqzCbEdx.Ha0jIIxXkNjh',
+        ]
+        config_file = directory / '.coveragerc'
+        for file in [*data_files, config_file]:
+            file.touch()
+
+        remove_debris_for('coverage', directory)
+
+        assert not any(file.exists() for file in data_files)
+        assert config_file.exists()
+
+
 def test_detect_debris_in_directory():
     """
     Does ``detect_debris_in_directory()`` identify debris artifacts?